Added HttpStatusDao - checks HTTP status of provided URL

Conflicts:
	module/Dashboard/Module.php
Changed HttpStatusDao to support Number widget instead of Error widget, better error handling
Modified Readme
Merge pull request #15 from Aftonbladet/HttpStatusDao

Http status dao
Merge branch 'upstream'
Merge branch 'master' into devils-dashboard

Conflicts:
	module/Dashboard/Module.php